Electric furnace.



No. 664,333. Patented Dec. la, |900.

J. M. MGREHEAD.

ELECTRIC FURNACE.

(Application filed Dec. 12, 1899.; (No Model.) 2 sheets-sheet 1.

Patented'Dec. I8, |900. J. M. MUREHEAD. ELECTRIC FURNACE. (Application filed Dec. 12, 1S99.\

(No Model.)

,25M/wb. SSM w www?. auw. 9595.415, @BMM UNITED STATES PATENT OFFICE.

JOI-IN M. MOREHEAD, OF CHICAGO, ILLINOIS, ASSIGNOR TO TllE UNION CARBIDE COMPANY, OF SAME PLACE.

ELECTREC FU RNACE.

SPEUIFICATION forming part of Letters Patent No. 664,333, dated December 18, 1900.

Application lecl December 12,1899. 'Serial No. 740,048. (No modei.`

"o @ZZ whom it' may concern.'

Be it known that I, JOHN M. MOREHEAD, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Electric Furnaces, of which the following is a specication. 1

The object of the invention is to provide for the exclusion of air from the furnace,whereby the evolved carbon-monoxid gas is led off unburned, thus obviating destructive heating of the electrodes and preventing the expulsion of large quantities of dust. To this and other ends hereinafter referred to the invention, stated in general terms, comprises an electric furnace consisting of a closed hood and a furnace-bottom movable in respect to each other and means or devices for retaining a packing of material between these two elements, which packing excludes air and directs the evolved gas into the hood, and it further comprises the improvements hereinafter described and claimed.

The nature, characteristic features, and scope of my invention will be more fully understood from the following description, taken in connection with the accompanying drawings,forming part hereof, and in which- Figure lis a central sectional view of one type of electric furnace embodying features of the invention. Fig. 2 is a perspective view of portions of the furnace shown in Fig. l; and Figs. 3 and et are respectively a side view, principally in section, and a front View of another type of furnace embodying features of my invention.

In a furnace embodying features of my invention there is a hood which collects the gases that are evolved, and through this hood such gases are led away without being permitted to mingle with air, and there is also a movable furnace-bottom which is shifted to- Ward or away from the electrodes l in order to regulate the process, and there is also provision for retaining a packing between the hood and the movable furnace-bottom. This packing permits of the movement of the furnace-bottom and of the pig 2 in order to adjust and regulate the operation, and it also excludes air from the zone of reduction and from the hood, so that the gas evolved as carbon monoxid is not permitted to mingle with air. It therefore may not burn, and its volume is small compared with what it would be if it were permitted to burn with air. The absence of burning gas in the furnace prevents undue heating' of the carbon-holders and carbons, and the reduction in volume of the gas escaping from the furnace very materially diminishes the quantity of dust escaping from the furnace, which is a very important consideration. Besides this the carbon-monoxid gas may be led away from the furnace and consumed or used to do useful work as contradistinguished from destructive and wasteful burning in the furnace.

In Fig. l, 3 is the hood, and 4t is the movable furnace-bottom. The hood 3 is provided with an inlet, as 5, for the raw material,which is usually pulverulen t, and with a gas-offtake, as 6. 7 is a removable cover-plate, and S is a hinged lid that may be opened for the insertion of a poker or like implement, as required. Between the hood 3 and the furnacebottom 4t there is a packing 9, which prevents the ingress of air to the hood and permits of movement of the pig 2 and of the furnacebottom a and also excludes air from the hood, as has been described. This packing may consist of the raw material, and it is held to place by means of the hook-like retaining devices lO, which are pivoted in rows, as shown in Fig. 2, and arranged all around the furnace. By their weight these devices operate to hug the pig without interfering with its upward and downward movement, and therefore retain the packing 9 in position. ll represents clamping devices that are useful for holding up the upper portion of the pig while the lower part is being removed.

In Figs. 3 and it, l2 is the hood, which is provided with a gas-offtake 13. le is the movable furnace-bottom, and l5 is a chute through which the raw material is introduced. The raw material is introduced into the hood l2, but not necessarily through the top or side walls thereof, and it gravitates all around it, and limited quantities may be worked in under the hood, if necessary, by means of a poker. That portion 16 of the raw material IOO which lies about and around the skirt of the hood constitutes the packing and is held to place by the Walls 17 of the furnace-bottom and permits of the described movement of the pig and also excludes air.

It will be obvious to those skilled in the art to which my invention appertains that modiications may be made in details without departing from the spirit thereof. Hence l do not limit myself to the precise construction and arrangement of parts hereinabove set forth, and illustrated in the drawings; but,

Having thus described the nature and objects of my invention, what I claim new, and desire to secure by Letters Patent, is

l. An electric furnace provided with a hood having gas-tight sides and top and having` an opening in the bottom for the removal of the product, conductors of opposite polarity projecting through the hood, means for embedding the skirt of the hood in packing material and thereby establishing and maintaining a seal 'for preventing ingress of air to the hood and for directing and confining gas in the hood, and means for removing` gas from the hood, substantially as described.

2. 1n an electric furnace having electrodes a gas-hood depending over the electrodes and provided with pivoted retaining devices depending around the skirt and provided with means for holding a part of the charge, substantially as described.

3. An electric furnace provided with a gascollecting hood having a gas-offtake and with conductors of opposite polarity depending through the hood, and with means for embedding the skirt of the hood in the raw material and thereby establishing and maintaining a seal for preventing ingress of air to the hood and for directing and confining gas in the hood, substantially as described.

In testimony whereof I have hereunto signed my name.

JOHN M. MOREHEAD.

In presence of- GRACE B. HURLBUT, W. J. JACKSON. 

